1

Life After 60 Long Term Nuclear Power Plant

Operations

Zachary E. Schriver

Purdue University

2012 Washington Internships for Students of

Engineering

Sponsored by the American Nuclear Society

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Acknowledgements

Thank you to all who contributed advice, knowledge, and guidance to this paper. I

would especially like to thank the following people:

Dr. Alan Levin for his extensive reviewing and commentaries on everything that

culminated into this paper, as well as overall information and guidance on

various topics.

Dr. William Behn for his role as a mentor for this internship program, and for

planning and organizing the experiences throughout.

Jason Remer and Martha Gow at the Nuclear Energy Institute for guidance and

resources for this paper.

The rest of the NEI staff for providing me with office space and creating a

friendly environment, specifically Michael O’Connell; Carol Berrigan; Elizabeth

McAndrew-Benavides; and Richiey Hayes.

The Washington Internships for Students of Engineering Program for providing

me with the opportunity to intern in Washington D.C. and discover the

intersections of technology and public policy.

The American Nuclear Society for sponsoring my appointment to the WISE

program.

All of the writers, researchers, organizations, agencies, and commissions whose

works I have utilized in the assembly of this policy paper.

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Executive Summary

This paper examines the proposition of a second round of license renewals for

commercial nuclear power plants from sixty to eighty years. Challenges and considerations that

are necessary to take into account during a transition to long-term operations such as those of

a technical, economic, public, and environmental nature are taken into account.

The aging of the current fleet of commercial nuclear reactors in the United States has

prompted a first round of license renewals that have been approved by the Nuclear Regulatory

Commission over the past decade. These reactors that hold renewed licenses will see them

begin to expire just before 2030, when the DOE estimates the U.S. will be demanding 30% more

electricity than what is generated today.

As nuclear energy makes up 20% of electricity currently produced in the U.S., this must

not be lost as the nation continues to diversify its energy portfolio; stepping up renewables and

phasing out fossil generation over the coming decades.

Pursuing second license renewals on a national scale would maintain over 100,000

industry-related jobs for an extra 20 years, which contribute in large amounts to the local,

state, and national economies. Over that extra time period, greenhouse gas emissions equal to

that of every passenger car in America (2010) can be avoided each year with the current

reactor fleet. There are also methods and technologies available that can keep nuclear power

plants operating safely through a second license renewal period.

Several actions that would augment long-term nuclear operations should be initiated. A

comprehensive national energy policy should be composed by the Department of Energy. This

plan should emphasize low or zero-emission forms of electricity generation, while drawing

down the amount of fossil generation in the United States. Advanced monitoring equipment

and techniques should be utilized to accurately develop the states of different equipment

within the plant. Communication between plant operators and plant host communities should

continue, or even increase. Spent fuel must be dealt with, and funding should increase for the

entities researching aging processes with these reactors.

With the right oversight and regulatory processes in place, second license renewals from

sixty to eighty years can solidify currently operating nuclear power plants in their place amongst

America’s diverse energy generation portfolio. These power plants will operate alongside new

construction and new technologies, providing a clean and safe form of electricity generation for

decades to come.

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Table of Contents

Acknowledgements .................................................................................................................................. 2

Executive Summary .................................................................................................................................. 3

Table of Contents ..................................................................................................................................... 4

List of Abbreviations ................................................................................................................................ 5

1. Current State of Nuclear Operations ............................................................................................... 6

2. Regulatory History & Basis ......................................................................................................... 8

3. Challenges and Concerns for a Second License Renewal ........................................................ 11

3.1 Technical Considerations ........................................................................................................... 11

3.1.1 Main Reactor Components ................................................................................................ 11

3.1.2 Steam Generators............................................................................................................... 15

3.1.3 Concrete Structures ............................................................................................................ 16

3.1.4 Cabling/Controls ................................................................................................................. 17

3.2 Economic Concerns .................................................................................................................... 18

3.3 Public Support ............................................................................................................................ 23

3.4 Environmental Concerns ............................................................................................................ 24

3.5 Spent Fuel Concerns ................................................................................................................... 27

4. Policy Alternatives .......................................................................................................................... 29

4.1 Fossil Fuels ................................................................................................................................. 29

4.2 Small Modular Reactors ............................................................................................................ 31

4.3 Renewable Technologies ........................................................................................................... 33

4.4 New Reactor Construction ........................................................................................................ 34

4.5 NRC Regulations and Conformity ............................................................................................. 35

5. Policy Recommendations .............................................................................................................. 37

Bibliography................................................................................................................................................ 41

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List of Abbreviations

ACRS – Advisory Committee on Reactor Safeguards

AEC – Atomic Energy Commission

BWR – Boiling Water Reactor

CFR – Code of Federal Regulations

DOE – Department of Energy

ECCS – Emergency Core Cooling System

GALL – Generic Aging Lessons Learned (Report)

GHG – Greenhouse Gases

INPO – Institute of Nuclear Power Operations

MWe – Megawatts Electric

NEI – Nuclear Energy Institute

NEPA – National Environmental Policy Act

NPP – Nuclear Power Plant

NRC – Nuclear Regulatory Commission

NWF – Nuclear Waste Fund

PWR – Pressurized Water Reactor

SMR – Small Modular Reactor

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1. Current State of Nuclear Operations

Since the 1950’s, nuclear power has driven the United States towards a cleaner,

more energy secure future. Begun in Shippingport, Pennsylvania in 1958, commercial

nuclear generation can now be found from coast to coast, with 104 reactors located in

31 different states [1]. This large build-out of the nuclear fleet can be seen in Figure 1,

and has allowed nuclear power plants to contribute nearly twenty percent of the United

States’ electricity generation needs steadily since 1990 [2]. The fleet is aging however;

the average age of a power reactor in the US is 32, and the oldest operating reactor,

Oyster Creek in New Jersey, is approaching 43 years of age. These reactors were initially

licensed for 40 years of operation, and over 75% have already been extended to 60

years by the Nuclear Regulatory Commission (NRC) [3] [4] [5].

Figure 1: U.S. Commercial Nuclear Reactors (U.S. NRC)

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By 2035, the Department of Energy (DOE) expects energy demand to increase

nearly 30 percent in comparison to what it was in 2008, far surpassing the United States’

current generation capability [6]. Current NRC-approved extended licenses will begin

expiring in 2029, leaving the nation with a dwindling supply of reliable base load power

in times where it will be needed most. This could lead to ten percent of U.S. nuclear

plants closing by 2030, and forty percent by 2035 as their 60-year licenses expire [7].

Offering a second license renewal program that would extend reactor life from 60 to 80

years would solve this problem (shown in Figure 2), securing nuclear generation as a

safe, economical, and environmentally and socially viable source of electricity for

decades to come.

Figure 2: Projected U.S. Nuclear Capacity with first and second License Renewals (U.S. EIA)

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2. Regulatory History & Basis

Following WWII, and coming out of Eisenhower’s ‘Atoms for Peace’ program, the Atomic

Energy Act of 1954 (AEA) set the conditions for the emergence of the commercial nuclear

generation industry. Previously, technical information and licenses for possession of nuclear

materials were very restricted, usually to military use. The AEA put in place provisions in the

areas of information control and patentability for nuclear technology, which was aimed at

making nuclear energy a force for the general welfare of the people. This allowed for private

investment into the development of nuclear technology and electricity generation methods, and

encouraged the involvement of private nuclear industry. The AEA also established the license

period for nuclear reactors to be, “not exceeding forty years”, and allowed for the possibility of

license renewals in the future [8].

The Nuclear Regulatory Commission spawned from the Energy Reorganization Act of

1974 which instituted a new regulatory system, separating regulatory responsibilities (NRC)

from those of industry promotion (DOE) and designating civilian programs as the NRC’s

regulatory responsibility. The NRC currently holds jurisdiction over all reactors, materials, and

waste (with the exception of DOE laboratories and military facilities) in the United States, and

issues and maintains licenses for facilities dealing with those items [9]. From the AEC days, the

initial reactor license period has stayed at forty years with the option to renew at an appropriate

time. This initial time period was selected for economic and antitrust reasons, but because it

was selected, that was the time period that many plant components were engineered for [8].

Over nearly the past two decades, the end of the original forty year terms had drawn

near, and the NRC reacted appropriately; establishing part 54 of Title 10 of the Code of Federal

Regulations (10 CFR 54) in 1991. This established essential safety requirements for license

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renewal, and included definitions for age-related degradation. Under these regulations,

operators of these plants must prove to the NRC that their facilities are in a state that is

safe to operate until the sixty year point by completing an application for license

renewal. These applications are then reviewed by NRC staff and the Advisory Committee

on Reactor Safeguards (ACRS). Combined with select on-site inspections, these

application reviews are conducted to ensure that continued operation of the facility can

be accomplished with reasonable assurance of adequate protection of the environment

and of public health and safety. In 1995, part 54 was amended to streamline the regulatory

process, and to bring more attention to managing the deleterious effects aging can have [10].

These changes and restructuring of part 54 were intended to be applicable for the first period of

extension, from forty to sixty years of operation.

In the NRC’s regulations, there is technically no limit to the amount of times that the

license for a reactor can be renewed, provided that the operators can sufficiently prove that

they have kept the facility and equipment in a safe operational condition, and will continue to

do so for the duration of the license. The NRC has produced several reports on aging equipment

over the years, and one has attempted to encapsulate a great deal of relevant information for

use in the discussion of license renewal. The Generic Aging Lessons Learned (GALL/NUREG-

1801) report was developed to evaluate if current programs were adequate for managing aging

plant infrastructure. This has served as a basis for NRC review of license renewal applications,

and contains many recommendations for review for NRC staff [11]. This report has been

subsequently revised and reissued several times.

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These revisions have caused issues with the implementation of NRC regulations.

For instance, the NRC renewed the licenses of the Ginna and Point Beach plants in 2004

and 2005, respectively. In between these renewals though, the NRC revised its license

renewal standard review plan and the GALL report. Within these revisions were

requirements for plants coming up for their first license renewal to address an aging

management program for Alloy 600 components within the reactor coolant system.

These requirements were applied to the Point Beach plant but not to Ginna. There are

also now environmental regulations instructing plants to have a cooling tower,

decreasing the need for water from an existing body, which are not enforced on those

plants built before the National Environmental Policy Act (NEPA) was established. A

good example of this would be the Salem and Hope Creek units, located on the same

site in New Jersey. The older Salem units rely on once-through cooling from the

Delaware River, while the newer Hope Creek plant was required to build a cooling

tower, offsetting a significant amount of water diverted from the river. No retroactive

enforcement occurred. These grandfathering actions can create an inconsistent

regulatory field that is difficult to work with at times [12].

Since several reactors are already into the first period of extended operation (forty to

sixty years) and the rest are drawing closer, the possibility for equipment degradation

continually increases. Many concerns, such as what really constitutes safe operational

conditions, if aging components require strict limitations, and if a renewed license is an

economically viable decision for the operating company become important questions to be

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answered. Though the NRC is currently anticipating no changes to Part 54 regulations, research

answering these questions should be done before any license is renewed again [13].

3. Challenges and Concerns for a Second License Renewal

Proposed license renewals carry with them a multitude of issues, as each nuclear

power plant (NPP) and surrounding area are a unique situation due to the particular

plant’s construction, operation, and community. Due to these particulars, there are a

few significant groupings of life-limiting concerns that will have to be overcome for

nearly all renewal applicants. These are concerns involving technical, economic, social,

and environmental considerations.

3.1 Technical Considerations

Due to the unique environment that is a nuclear power plant, there are certain

considerations that must be addressed here that will not be seen in other industrial

environments. The NPP environment differs from that of a traditional power plant in that many

components are exposed to a high neutron fluence, a corrosive environment due to boric acid,

and a constant high-temperature cycle. Such intense factors can have deleterious effects on

many reactor components. In the interest of safety, it is paramount to understand the

risks caused by such an environment over time, and develop methods to mitigate their

effects.

3.1.1 Main Reactor Components

The components of the reactor itself are the ones that can experience the largest

amount of damage over a long period of operation. The pressure vessel, vessel head,

and reactor internals are submitted to extended periods of time in an extremely hostile

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environment. These circumstances can lead to embrittlement and metal corrosion.

Embrittlement is a loss of ductility in a metal, making it prone to cracking or ultimately

to failure. As neutrons bombard the metals of a pressure vessel, they knock atoms out

of place, changing the microstructure and creating internal stresses within the metal.

This results in a loss of ductility for the metal, and makes it brittle [14].

The internals of a reactor refer to things such as fuel support structures, control

rod guides and nozzles, separators and dryers for boiling water reactors (BWRs), and

other internal non-fuel machinery and parts. Due to their location inside the core, or in

very close proximity, they will see a significant damaging effect from their environment.

Strong neutron bombardment and wear over time are concerns for this equipment. For

license renewal considerations, these components will have to be verified as needing to

be replaced or not, and then whether a replacement is viable. Due to the lack of explicit

knowledge on these component lifetimes, a case-by-case examination will have to be

done [15].

The reactor vessel head is a component that, while large and expensive, has

been replaced on numerous reactors in the past. This component is critical in its

purpose of sealing the reactor vessel and allowing the correct pressure to be reached

for operations. Usually replacement of the vessel head is done because of an initiative

to refurbish the plant, as was the case in 2006 at the Fort Calhoun NPP. However, due to

the adverse environment it is a part of, that is not always the case. In 2002, a large

amount of corrosion was found on the vessel head of the Davis-Besse NPP. This was

found to be the result of a primary coolant system leak, allowing boric acid to collect

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and degrade the carbon steel of the vessel head to alarming levels. Davis-Besse was not

the first plant to report boric acid corrosion on reactor components, nor will it probably

be the last [16].

Corrosion-caused component wastage is a serious issue that must be paid

attention to when considering extended operations. For the vessel head, replacement is

the most viable option. Repairing such a critical structure would not be without

criticism, and as the vessel heads on many reactors have now been replaced mostly

without issue, there is a growing wealth of knowledge and experience on the topic [17].

Thus, replacement should be seen as a viable option for ensuring continued operations

[18].

The reactor pressure vessel itself is the last critical piece of main reactor

components. The vessel is the most important piece, as it is the first and strongest

barrier between the nuclear fuel and the outside environment. Consisting of low-alloy

steels up to nearly 8” thick, sections are joined welded together to form the whole

vessel. After initial construction, vessels undergo various treatment processes to ensure

initial strength and toughness of the metal used. [14].

This toughness characteristic of the vessel can become questionable over long

periods of time in a high neutron fluence. These neutrons emitted from the reactor core

can vary in energy spectrum from one to about 2 million electron volts, and it is the

high-energy neutrons that can cause the most material damage [14]. Over sixty years of

operation, these high energy neutrons will impact the vessel countless times. This large

amount of flux over time deposits an equally large amount of energy into the metal, and

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can change the microstructure significantly. Embrittlement is a large concern for these

vessels due to their importance and the constant pressure load that they carry. Though

embrittlement alone may not cause a vessel failure, it may aid in combinations of failure

events. Pressurized thermal shock is a term used to describe the effects on the metal

vessel that would occur in a standard emergency scenario. If the emergency core

cooling system (ECCS) were ever to activate, it would directly inject cool water directly

into the pressurized reactor core. This drastic cooling of the vessel from operating

temperature (290 C and 550 F) down to ambient would severely stress the vessel,

possibly leading to significant cracking or catastrophic failure [14].

There are options for addressing these concerns, however. Currently, the two

possibilities on the table are vessel replacement and annealing. Replacement of the

vessel itself has been seen as technically possible for some time now, though considered

prohibitively expensive in most cases. Annealing the vessel though, has seemed

promising. Experiments run in joint collaboration between Oak Ridge National

Laboratory and the Russian Research Center-Kurchatov Institute have shown marked

recovery of steel samples. These samples were chosen for their similarity to metals used

in reactor pressure vessels (US and Russia), and three of the four were welded to model

that interaction as well. The samples were irradiated in test reactors to simulate a high

neutron fluence, and then annealed for varying amounts of time to determine the

benefits. It was found that the materials exhibited the possibility of nearly full toughness

recovery after undergoing annealing treatment at 454 degrees C (850 degrees F), and

that the longer the anneal lasted, the more effective the recovery [19].

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Applying this experimental result to a full scale pressure vessel could prove very

difficult, though still possible. The process itself is able to be done in accordance with

NRC regulations, as requirements for thermal annealing of pressure vessels are laid out

in Title 10, Part 50.66 of the Code of Federal Regulations. If an annealing repair to the

pressure vessel was decided to be the correct route to take for a plant life extension,

many considerations would have to be made for surrounding equipment within

containment during the annealing process, as it could easily be damaged by residual

heat. Like vessel replacement, annealing may prove to be too costly to implement, but

the technology is available and so it remains an option for preventative maintenance

towards a second license renewal.

3.1.2 Steam Generators

Steam generators on pressurized water reactors (PWRs) are another component

that must be examined and dealt with. Of the 104 operating nuclear reactors in the

United States, 69 are PWRs and have from two to four steam generators per unit [6].

These generators are utilized to transfer heat from the radioactive primary coolant loop

to the secondary non-radioactive coolant loop, turning the coolant (water) to steam in

the process. This steam is then used to turn an attached turbine to create electricity.

To accomplish this, the primary loop coolant is split into between 3,200 and

15,500 (depending on make and model) tubes of 19-25mm diameters inside the steam

generator. The secondary loop then pumps water over these hot tubes, removing the

heat and turning the water to steam. Over time, these components can develop

numerous problems, ranging from tube denting, fatigue cracking, pitting, tube wear,

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and general wastage/corrosion. Many of these issues were initially traced back to the

alloy utilized in the first generation of steam generators, Inconel 600, though they can

plague all installations over time [20].

While considering adding an additional operating period of at least twenty years,

steam generators must be examined again. If individual tubes are degrading, they can

be repaired or plugged (if the degradation is severe). If a certain amount (usually around

20%) of the tubes end up needing plugged, or otherwise exhibit excessive wear,

replacement of the generators or plant shutdown are the only real options. Often to

ensure extended operations, an operator will proactively replace the generators.

Though costly, this method ensures that the plant will continue to maintain safe

operations [20].

3.1.3 Concrete Structures

Some of the most critical structures in a NPP besides the reactor itself are in the

form of vital reinforced concrete structures. Reinforced concrete is a mixture of

concrete and rebar and is used for its structural strength, strong ability to shield

radiation, and normally long lifetime. Structures dependent upon this concrete in a

modern NPP include the containment dome (prestressed), plant base mat, and other

support structures. As the most important structures are those utilized in safety roles

and prevention of radiation release to the environment, the aging of this material is a

top concern among those investigating a possible second license renewal [21].

Reinforced concrete used in these structures can be subjected to a variety of

deteriorating forces in a plant environment. Chemically they can suffer leaching, sulfate

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attack, and acid and salt buildup. Physically there are freeze/thaw cycles, thermal

exposure/cycling, abrasion, and fatigue or vibration. These forces can cause issues

ranging from base mat cracking, to corrosion of steel reinforcements, to freeze/thaw

damage to the containment dome structure. With these effects in mind, inspection is an

important part of life-cycle management for these components, however many

components can be viewed as inaccessible for monitoring (concrete base mats for

instance). Many emplaced concrete safety structures are also considered economically

unfeasible to replace, due to their integration into the plant systems, or because of the

expense of repairing reinforced concrete (considering embedded rebar) [22].

To remedy some of these concerns, more detailed inspection methods and

evaluation techniques have developed over time. Nondestructive evaluations have

evolved, allowing inspectors to reach conclusions on the health of these critical

structures without damaging them. This is done via a combination of ultrasonic

measurement and visual inspection. For new reinforced concrete structures, emplaced

sensors are being considered that would be implanted within the structure, providing

operators with a constant data on the status of the structure [23].

3.1.4 Cabling/Controls

Cabling and controls within a power plant are one of the more extensive and

important system components. Responsible for power transmission, data flow, and

overall plant control, various cable networks find themselves in all environments of the

plant [24]. Like the reactor internals, these systems can also find themselves in areas of

high temperature, high radiation, and even high humidity and corrosive environments.

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To ensure proper plant operations into the future, this ‘nervous system’ of the plant

must be kept in good health.

Not all cables are located in deleterious environments, but for those that are,

various managing processes are now known that can make monitoring and

management of their aging easier. Towards the goal of nondestructive evaluation,

various methods of diagnosing cable health exist. These can include a surface hardness

test; which looks for cable jacket embrittlement over time, an ultrasonic examination;

which examines cable jacket integrity, and an optical evaluation; useful as jacket color

change often denotes aging material [24]. Cables in high duty environments can also be

assessed for heating degradation, and evaluated as to their overall heath. Submerged

cabling is a main concern for degradation, as a fault there could create unwanted

discharge and circuit noise [25].

3.2 Economic Concerns

Nuclear energy has not always made the most financial sense from an operations

standpoint. In the early years of the technology, the industry was plagued by inflated

budgets and schedules during construction. Capacity factors were also initially low, still

sitting below 65% in 1988 when the percentage of nuclear powered electricity

generation in the U.S. first hit 20%. It took over ten more years for them to hit the 90%

levels were they have been hovering for about the past decade [2]. This increase is the

direct result of a large amount of accumulated operator experience, the NRC’s shift

from a construction to operations focus, and the Institute of Nuclear Power Operations

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(INPO). With those changes, the achieved 90% capacity factors of today reflect little

more than the down time needed for refueling and maintenance [2].

The nuclear power plants operating today are large generators of affordable

energy. Data from the Nuclear Energy Institute (NEI) in figure 3 shows how over the last

17 years, total production costs (fuel, operations, and maintenance) for the main forms

of electricity generation in America have fluctuated . Petroleum and natural gas prices

have fluctuated the most due to a marketplace that has been shown to be highly

volatile. Their prices have shifted mostly due to fuel costs, not because of operations or

maintenance. The costs of nuclear and coal powered electricity generation however,

have not changed significantly over the same time period, with nuclear edging out coal

for cheapest overall production costs in the last decade. The inherent stability of nuclear

fuel costs helps reduce the price of electricity for consumers, and keeps it at a

predictable level [26].

Figure 3: Total Production Costs of Various Electricity Generation Methods (NEI)

0.00

5.00

10.00

15.00

20.00

25.00

Co

st (

cen

ts p

er

kilo

wat

t-h

ou

r)

Year

1995-2011 Total Production Costs

Coal

Gas

Nuclear

Petroleum

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Nuclear power also shows definite benefits for the surrounding communities. A

current single unit plant can employ anywhere in the range of 400 to 700 permanent

workers in full-time positions [27, 26]. The average plant in the United States generates

approximately $470 million in sales of goods and services in the local community and

nearly $40 million in total labor income annually. It can also generate up to $16 million

in state and local tax revenue each year, paying for public goods such as schools, roads,

and local infrastructure. Due to these effects, analysis shows that for every dollar spent

by the average nuclear plant; approximately $1.04 is created in the local economy,

$1.18 in the state economy, and $1.87 in the national economy [26].

On the national level nuclear is a positive force as well. Every year overall in the

US, the nuclear fleet generates a large amount of economic value and revenue. This is

approximately $40 to $50 billion each year, while employing over 100,000 people

nationally. Currently operating nuclear plants also have the interesting characteristic of

employing a large number of people for each megawatt of electricity generated, a

definite benefit in the current economic climate. In figure 4 shown below, nuclear

employment per megawatt is second in this regard only to solar photovoltaic

technology. Due to nuclear technology’s sheer size in comparison though, it is clear that

nuclear has a much larger effect in the employment arena [28].

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Figure 4: Jobs per Megawatt Electric for Various Generation Industries (NEI)

For these reasons, license renewal of currently operating reactors makes sense,

assuming that the plant itself meets the regulatory requirements of Part 54 prior to the

second license renewal application. If a major overhaul of plant systems is required

(vessel head, steam generators, pressurizer, associated maintenance), then a large

capital investment will become necessary. These investments have occurred at some

stations already, Fort Calhoun being a notable example, where Omaha Public Power

District (the plant’s owners and operators) spent $417 million on refurbishment in

preparation for a license renewal [7]. In addition to the capital costs, plant outage time

must also be taken into account. Using the Fort Calhoun example again, their outage for

refurbishment lasted 85 days. Each one of these days being a day of missed profit for

the utility, where electricity must be purchased from another source. When steam

generator replacements were first performed, in the late 1970s, the project required

more than 300 days to complete. As experience has been gained and such projects have

become commonplace, the completion time has been dramatically reduced, to as little

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as 40 days in 2007 (Diablo Canyon Unit 1) [20, 29]. Compared to a normal refueling

outage which clocks in at an average of 39 days in 2006, these refurbishment outages

are comparable, and operating companies should be able to prepare financially [30].

These types of capital investments for critical equipment are occurring though.

In 2010 alone, the industry invested approximately $7 billion in projects to upgrade and

maintain plant systems. Over the past two decades, the amount spent on upgrades and

maintenance has been on an increasing trend, due to the onset of the first round of

license renewals. Considering decisions made to pursue second round license renewals,

equipment investments are expected to continue increasing. Figure 5 shown below

details this increase in expenditures [7].

Figure 5: U.S. Capital Investments by the Nuclear Industry (Electric Utility Cost Group)

These costs of preparation for the future, along with the processes involved, play

a large factor in the decision of whether or not to attempt to apply for a plant license

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renewal. If the plant is completely paid for and wholly owned by the utility, it would

make more sense to invest the upfront costs of preventive maintenance and maintain

the plant as a profit generator for the next 20 years. If underlying problems are found

that would prove too costly to fix however, the owner may decide to retire the plant.

Public perception and/or opposition to nuclear reactors can often be a contributing

factor to this decision as well.

3.3 Public Support

Nuclear generation of electricity has had a varied history of public perception.

After the disasters at Three Mile Island and Chernobyl in the 1980’s there was a

significant drop in public approval. Immediately afterwards though, approval was on the

rise, and has maintained this upward trend consistently until the Fukushima disaster

occurred in Japan in 2011. Before the end of the year though, public approval was rising

again [31]. This trend shows the strength of the confidence that the American public has

built towards the nuclear industry over the past decades. This support is an important

factor to consider for a second license renewal, as a supportive community will not

stand in the way of a project’s continuance.

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Figure 6: Favorability of Nuclear Energy to the General Public, May 2012 (NEI)

To contest opposition to nuclear energy, the nuclear industry as a whole does a

very good job of putting facts and figures that are truthful and support the industry out

into the public domain. If the truth of the matter though is that these may not

accomplish what is intended, it seems that a different course of action could be a more

prudent choice. In the words of Dr. Daniel Aldrich, an associate professor of political

science at Purdue University, “Nuclear power is not an engineering problem; it is an

issue of communication and engendering support of the people”. This being said, the

support of the people is paramount to maintaining a key social structure that is

welcoming to the long-term continuation of power plant operations.

3.4 Environmental Concerns

In 2011, the United States generated approximately 4.1 trillion kilowatt-hours of

electricity, with over 790 billion kilowatt-hours being from nuclear generation [32, 33].

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This massive amount of electricity generation has been accomplished in a clean,

environmentally friendly manner. In that same year, 1.41 million tons of sulfur dioxide,

540,000 tons of nitrogen oxides, and over 613 million tons of carbon dioxide were

avoided in the United States by the use of nuclear power in lieu of coal [34]. This is

roughly the equivalent to 118 million cars on the roads – nearly all passenger cars in

America [34].

As the nuclear energy industry in America is responsible for over 63% of the

nation’s emission-free generation (meaning no CO2, NOX, or SO2 produced during

operations), it seems imperative to make a case for maintaining, if not expanding, this

environmentally responsible industry. The industry also has a strong track record in

being responsible stewards of the environment where there are plants located. Many

utilities have taken to becoming stewards of national wildlife preserves on land near

their plant, or creating programs to help natural species or conserve resources. In

Arizona, the Arizona Public Service-run Palo Verde plant has developed a unique cooling

system. In the interest of conserving water, the plant purchases reclaimed sewage for

the plants cooling water. The Pilgrim plant in Cape Cod, Massachusetts, has invested

heavily in many fish hatcheries for species like winter flounder, which have been

declining in number. Fort Calhoun in Nebraska hosts beaver, muskrat, and mink in its

managed wetland wildlife preserves. Many plants share these same characteristics and

desire to enhance and protect the wildlife around them [35].

Though many parts of the overall life cycle of nuclear energy do release

greenhouse gases, nuclear still tends to be very much cleaner than other forms of

26

generation. In 2000, the International Energy Agency found in a study that the average

life cycle carbon emissions for nuclear energy were between 2 and 59 grams of carbon

dioxide per kilowatt-hour. These sources include uranium mining and processing,

construction of facilities, and all forms of transportation. In that study, nuclear was

second only to hydropower, whose life cycle emissions were rated as between 2 and 48

grams per kilowatt-hour. In comparison, the life cycle of a natural gas fired plant ranged

from 398 to 511 grams carbon dioxide equivalent per kilowatt-hour. The Department of

Energy shows similar findings in figure 7 below, and states that, “Collectively, life-cycle

assessment literature shows that nuclear power is similar to other renewables and

much lower than fossil fuel in total life-cycle greenhouse gas (GHG) emissions.” Though

carbon emissions in the United States are still climbing, if there is any hope to rein them

in, nuclear power must be a strong part of that plan [36].

Figure 7: Life Cycle Emissions of Various Electricity Generating Technologies (NREL)

27

3.5 Spent Fuel Concerns

Each of the 104 commercial power reactors in the U.S. operates on what is

known as the ‘once-through’ fuel cycle. That means that fuel is installed into the core,

‘burned’, and then taken out and stored. When removed from the reactor core, the fuel

itself is dangerous to humans, and has such a high level of radioactivity that it is unsafe

to handle, and is hot enough that it must be actively cooled. The physical heat is from

the decay of fission products in the spent fuel. The fuel is then immediately placed in

the on-site spent fuel pool to cool. After at least 5 years of cool-off in the spent fuel

pool, the fuel can be moved into dry casks for storage (large concrete and steel

containers) or shipped off to a repository, were there one available. There is currently

no recycling capability in the U.S. for civilian nuclear fuel, though this spent fuel still

holds a large amount of usable isotopes [37].

Currently, spent fuel from nuclear reactors sits on-site. Every year approximately

2,000 metric tons of fuel leave reactors around the nation and enter a spent fuel pool,

located either inside containment, or in an auxiliary building [38]. These pools have

been holding fuel since the reactors began operating, and many have already reached

their capacity. Many operators are utilizing dry cask storage to create space within their

spent fuel pools for incoming fuel from the reactor, though most of them are only

offloading what is absolutely necessary from their spent fuel pools [37]. This means that

the pool stays at maximum capacity, and as old fuel is moved to dry cask, new spent fuel

immediately takes its place in the pool. Keeping these pools at maximum capacity can

give rise to potential problems during an accident scenario. Where there is more fuel,

28

there is more heat, and the closer together the spent fuel bundles are, the quicker the

pool’s water will boil away in the event of a loss of power, or station blackout. This is not

dissimilar to what was feared to be occurring at the Fukushima reactors during the

disaster in 2011. By moving spent nuclear fuel into dry cask storage before the spent

fuel pools reach capacity, operators can cut down on the amount of fuel sitting in the

pool, and thus increase the time until pool boiling in the event of a loss-of-power

emergency; giving responders more time to restore pool cooling [37].

Many reactors in the United States are beginning to hit the maximum capacities

of their spent fuel pools before forty years of operation. If not dealt with, this problem

will only compound itself through the first period of license renewal, much less the

second. The lack of a plan to deal with spent fuel by the U.S. government, while it still

forces utilities and operators to pay into the Nuclear Waste Fund (NWF), is not

promising. This fund is set up to provide funds for the government to move spent

nuclear fuel to a safe and secure national repository, and currently sits at around $24

billion. So far, it has not been utilized for disposing of the spent fuel, but rather for

studies and license applications pertaining to Yucca Mountain (which is no longer being

pursued). The fund continues to be paid into though, waiting for a spent fuel

management project that can make full use of it [39]. This could potentially change,

were the fund repurposed to provide funding for cask storage of nuclear fuel. A move

such as this would benefit not only the operators and the government, but instill more

confidence in the citizens as well.

29

4. Policy Alternatives

There are many alternatives to commercial nuclear power reactor relicensing

that can be considered as options today. As this paper considers the topic as a ‘yes or

no’ decision, alternatives will be considered to be affected by a decision of ‘no’ to

pursue extended operations. There are several ways to deal with the problems that

would be caused by a ‘dropping off’ of nuclear power from the national grid.

4.1 Fossil Fuels

The loss of ten percent of the U.S.’s nuclear power by 2030, and forty percent by

2035 could be handled by an increase in the burning of fossil fuels. This can be noted

immediately as the least sustainable of the alternative options. Replacing nuclear

capacity with fossil fuels would entail replacing not only the capacity of the 104

currently operating reactors, but also building out more fossil capacity to handle the

DOE’s projected 30% increase in electricity demand over 2008 values [6]. This is

obviously problematic on many levels, especially those that are concerned with

environmental preservation and greenhouse gas emissions. Coal and natural gas would

be the fuels of choice in this scenario.

Coal has always been an abundant resource in America, for years being the

dominant mode of electricity production [32]. Since it is highly abundant, it has also

been considered the cheapest form of energy for some time. The cost of coal is not only

monetary though, as it is also the largest source of pollutants in the nation, being

responsible for more than a quarter of all U.S. global warming emissions, and for 80

percent of those emissions from power plants. According to a Union of Concerned

30

Scientists report, a typical 500 MWe coal plant will burn nearly 1.2 million tons of coal in

a year, producing 2.9 billion kilowatt-hours of electricity. It also produces 3.1 million

tons of carbon dioxide, 8,250 tons of sulfur dioxide, 8,400 tons of nitrogen oxide, over

400 tons of small particulate, 600 tons of carbon monoxide, 100,000 tons of ash,

159,000 tons of sludge, and over 250 pounds of arsenic, lead, and other heavy metals

(based on 2009 industry average capacity factor of 66%) [40, 41]. The carbon and

nitrogen oxides are all contributors to global warming. Sulfur dioxide is a main cause of

acid rain and smog. Small particulate matter in the air can have a very damaging effect

on lungs when inhaled. Ash and sludge are remnants from the combustion process, and

while they don’t end up in the air, they will mostly end up in a landfill, occasionally

leaching into the environment. Though technology such as smokestack scrubbers have

cut down on sulfur emissions, carbon dioxide and the many other pollutants remain

unchecked with coal [40].

Natural gas would be a better fuel to utilize though, as it is the cleanest of the

fossil fuels. Natural gas has been increasing in abundance in recent years as methods of

extraction have matured, such as hydraulic fracturing, which allows previously un-

recoverable deposits of the gas to be extracted. This sudden ability to access more

reserves in the U.S. has greatly reduced the price of natural gas. Many states though are

currently beginning investigations into the safety and environmental responsibility of

fracturing, claiming that it can contaminate drinking water. Natural gas, which is

primarily methane, has also been known to generally leak from any system used to

transport it [42]. This methane leaking into the atmosphere can be many times more

31

effective at trapping heat than carbon dioxide, and would be a huge detriment to the

efforts in place to fight global warming. The decision to replace lost present and future

nuclear capacity with a natural gas solution would demand a large build out in supply

and distribution resources, which have been shown to leak up to 2.5% of the

transported and stored gas [42]. Though natural gas is cleaner than coal, comparatively,

it still is a large emitter of carbon and nitrogen oxides which largely affect the

atmosphere. This fact in itself should make natural gas an undesirable solution for long

term energy growth.

Oil still remains as an electricity generating fossil fuel. Lately though, it has seen

a steep decline in usage as petroleum prices have soared in recent years. It is currently

dropping rapidly in share of energy production across the nation, and is expected to

maintain that trend [32].

4.2 Small Modular Reactors

Small modular reactors (SMR’s) are gaining traction as an alternative to the large

and expensive power plants that we see in operation today. Most current reactors are in

the range of 900-1100 MWe production. Small modular designs maintain the basic

process of nuclear power generation, but scale it back to what is for some companies

and areas, a much more manageable scale. These designs range in electrical output

from between about 30-300 MWe, and represent a smaller capital investment than

their larger cousins as well. They are designed with a ‘modularity’ concept in mind,

which means there is an emphasis on building the plant components at a factory, and

32

then shipping them to be installed at their location. This saves on construction costs,

and brings the overall price down even further [43].

Small modular reactors would give operating companies the freedom to address

smaller sections of the power grid at a time, potentially adding a unit at one site, two at

another, and scaling the installations to match demand as they see fit. The smaller

capital investment also means that the company is in a much riskier position overall

when deciding to go the route of the SMR. These reactors could also be advantageous at

powering areas that have no connection to the grid whatsoever. Remote areas in the

Arctic or Antarctic could greatly benefit from having an independent, consistent power

source. Many companies are stepping up to the plate and currently designing their own

SMRs. Westinghouse, Babcock & Wilcox, NuScale, Holtec, and General Atomics are just

a few of the names getting involved. As of March 2012, three companies have shown

interest in constructing demonstration reactors at the DOE’s Savannah River site. These

actual tests seem rather far away though, even for the designs based on light water

reactor technology. A report done for the DOE in 2011 claims that most SMRs are only

10 to 20 percent through the engineering design phase, only limited cost data is

available, and no factory has yet progressed past the planning stages [43].

SMR’s could present a viable alternative to a second license renewal in the years

ahead. By the time that decisions would need to be made to renew a nuclear power

plant’s license a second time, SMR designs may have been approved by the NRC. At that

point it will likely become an economic decision for operating companies whether they

would invest in keeping a large, centralized power plant up and running, or whether a

33

distributed network of new, smaller plants (SMR’s) would make sense to pursue. SMR

designs have also been proposed as additions to currently operating plants. This could

be an option while still going through with a second license renewal to add generating

capacity to an already existing plant location.

4.3 Renewable Technologies

Renewable technology is one of the fastest growing segments of power

generation the world over. Composed of wind, solar, hydro, geothermal, and other

forms, renewables have the distinct characteristics of utilizing nature itself to produce

electricity. In this effort, they are operationally non-polluting, and the most-

environmentally friendly option for electricity production from a greenhouse gas

perspective.

Wind energy is popular as it uses the wind to turn fan blades that then turn a

turbine, generating electricity. There are many regions across the United States that

would be very suitable for wind energy, especially in the central plains states and

directly off the coasts. Hydropower is generated through adding turbines to dam

structures. As the water flows through the dam spillway, its moving momentum spins

the turbine. Hydropower on the larger rivers and lakes is a relatively constant source of

electricity. Solar power is generated through photovoltaics, or through concentrated

solar power. With photovoltaics, photons from sunlight can knock an electron off of the

metal atoms in a solar panel, creating a current. Concentrated solar reflects and focuses

the Sun’s rays to heat a medium (usually water) to utilize in the Rankine cycle.

34

Geothermal power relies on pumping water deep into the ground where it is heated,

and returning it as steam which is used to drive a turbine. These are all very progressive

technologies, and are a real consideration for augmenting future electricity generation

[44].

All of these technologies have their limits, however. Wind and Solar cannot be

used as a reliable base load power source, meaning that they are not reliable sources of

electricity that can be considered ‘always on’ as nuclear can be. Wind does not

constantly blow, and the sun is only out for half the day in the summer. Hydro offers a

consistent source of electricity, but no real aspect of expansion. Nearly all locations in

the U.S. where hydro could be a possibility are already sited. Geothermal has the same

restriction. There are a limited number of areas where the ground is hot enough to pipe

in water without having to drill excessively deep. Though these technologies will be

instrumental in strengthening the United States’ commitment to a lower-carbon future,

they will not be able to replace nuclear power [44].

4.4 New Reactor Construction

One possible alternative to license renewal would be the construction of a fleet

of new, 1000+ MWe nuclear power plants. This plan has a massive benefit in that new

and advanced reactor plants would be replacing the old, 1970’s-era technology. New

technology (Generation III and III+) such as Westinghouse’s AP-1000, GE’s ESBWR, or

Areva’s US-EPR would have significant safety and economic advantages over the

currently operating fleet of Generation II reactors. Concepts such as passive cooling

35

could now be utilized in some designs (completely or only in emergencies), and the

amount of piping and cabling is generally decreased as well, eliminating points where

system faults could occur. Emergency systems are also improved in new designs, and

containment structures have been updated. From the point of view of safety and

technological advancement, replacing the legacy power plants would make perfect

sense, but the financial burden may be too high.

At the Vogtle site, where two AP-1000 units are under construction currently, a

significant financial burden has been shouldered by the Southern Company. The cost of

the twin reactors is projected to be $14 billion total, or $7 billion per unit. Replacing the

10 plants that would go offline without a second license renewal by 2030 would cost

$70 billion, and the 40 that would retire by 2035 a conservative total of $280 billion.

Though this cost would not be borne by just one operating company, it could potentially

be high enough to put the option of plant replacement out of reach. In the current

economic climate this option remains uncertain, though that may change in the future

[45].

4.5 NRC Regulations and Conformity

Due to certain grandfathering and exemptions for various plants across the

nation, the NRC’s regulations are not enforced uniformly. This fracturing of the actual

implementation has the potential to severely degrade the efficacy of regulations

currently in place. Examples of this non-conformity that have occurred include plants

such as Ginna which was grandfathered past an Alloy 600 aging management plan

36

requirement for cooling systems, or for the Salem and Hope Creek units’ cooling tower

variance. A path to fix this would be re-examine current non-conforming situations, and

attempt to establish baseline conformity regulations, if possible. This approach has the

potential to leverage more plants onto the same regulatory plane, while still allowing

certain exemptions where they may be necessary. It could also allow a higher level of

confidence in the regulatory authority as well as with the operating plants themselves,

and can be considered an investment in the future of the industry as a whole.

Those benefits could have a very large expense attached though, and the

possibility exists that many operators would not take on that financial burden. Without

declaring regulatory conformity a desired course of action, some facilities are already

debating the economics of continuing into long-term operations. Many systems that

could need to be changed are integral to the construction of the plant as well, and

would take an exceedingly large investment of time and money to rectify. In that regard,

this conformity does not seem like an immediate possibility, and those exemptions will

stay valid through a second license extension for many operating nuclear plants. The

notion of decreasing these grandfathering situations however, should be looked into.

Though some plants are exempt from certain statutes with good reason, others may not

be as time progresses and more is learned from accumulated research and operational

experience.

37

5. Policy Recommendations

The United States should encourage the second term license renewal of

commercial nuclear power plants from sixty to eighty years. The long-term operation of

many of these facilities will be crucial to maintaining and advancing America’s energy

portfolio towards a cleaner and more renewable future. These extensions though,

should come in tandem with several other actions within the industry.

In a world where climate change is a prevalent issue, a large draw for nuclear

energy is its proven record of zero greenhouse emissions during operations, and of

extremely low life cycle emissions. To keep nuclear as such an attractive option in that

regard, attention must continue to be paid to cleaner sources of energy, and the

phasing out of older, higher-polluting sources of electricity such as coal, oil, and natural

gas. Nuclear energy offers a stable and predictable supply of base load electricity now

and will continue far into the future with the option of a second license renewal. It does

this with high capacity factors as well, ensuring the power will be there when it is

needed. If the United States embarks on a comprehensive energy plan that takes into

account these environmental, economic, and technical factors, nuclear can continue to

be a very large contributor to a future with much less emissions, and even grow to

encompass expanded clean energy production.

As these power plants age, it is necessary to make sure that they are being

supported and managed properly through this time. New methods of non-destructive

inspection and monitoring are being developed by industry laboratories, and should be

38

implemented. Replacement of critical parts, or other methods of refurbishment

(annealing of the pressure vessel for instance) should also remain a top priority,

especially when the decision to apply for a second license renewal is made. Funding for

research into these aging methods through the NRC, DOE, and EPRI must continue as

well. These actions will ensure that safety remains a top priority, keeping current

nuclear power plants a viable source of electricity for the nation through a proposed 80

year lifespan.

To continue a trend safety, the problems of spent nuclear fuel must be dealt

with. It is one of the few issues plaguing the industry that had still not been dealt with in

a timely manner. Nuclear plants that operate for an extended period of time via a

second (or even first) license renewal will be generating more used fuel than their used

fuel pools can handle. This fuel must be removed from the pools that are at capacity,

and make its way either to a national repository or interim storage in dry casks, both of

which represent safer, more secure storage options. This could be done by re-

appropriating the nuclear waste fund and using those monies to pay for dry cask

storage, moving the fuel from the relatively vulnerable spent fuel pools into much more

secure casks.

It is also imperative for the nuclear industry to build and maintain a rapport with

the towns and communities within which they operate. The nuclear industry is one of

several industries in the modern world that has the capacity to be severely hindered

should a large accident occur. From what has been seen though, public perception

39

ultimately also has the final say in activities of the industry. This is obvious after the

events of Fukushima, and throughout the US after Three Mile Island, when due to public

outcry and mistrust along with regulatory review, construction and expansion slowed

dramatically for a period of time. Since that period though, approval and the perception

of nuclear by the general populace has been increasing positive overall.

Many operators today have excellent relationships with their surrounding

communities, and those should not be taken for granted. Many plants pay for additional

community resources, such as new buildings for police and the fire department, new fire

trucks and police cruisers, parks and sports fields, and upgrades for other public goods.

These activities should be the gold standard, and what every operator tries to achieve

within its selected community. Each operating company needs to be aware of the

‘shared welfare’ that is the industry, and work to maintain that by keeping up a

favorable stance in the eye of the public. Increasing public perception combined with

continued industry communication efforts towards the public should create a positive

reception for a second set of license renewals.

Along with the required application reviews for a second license renewal, the

NRC should examine its own regulations and determine how or if they can be modified

to achieve a level of uniformity throughout the nation, for both old plants and new.

Though this conformity would be difficult, it should be considered a goal to be reached

over time. Situations of non-conformity should be re-examined and evaluated to be sure

that they are still relevant and responsible choices in the realm of long-term operations.

40

The NRC also needs to continue the research being done internally, at the DOE, and

within the industry to thoroughly examine the effects of materials aging in relation to

safety. Though there have not yet been any changes made to regulatory policy from the

first to second rounds of license renewals, there must be an informed decision made to

ensure that if any are required, they are responsibly included. These policy decisions can

help to ensure the safe future of the nuclear industry, and in turn the clean generation

of electricity in America for generations to come.

41

Bibliography

[1] IEEE Global History Network, "IEEE: GHN," 2012. [Online]. Available:

http://ieeeghn.org/wiki/index.php/Shippingport_Nuclear_Power_Plant. [Accessed 2 July 2012].

[2] Nuclear Energy Institute, "NEI: Nuclear Generating Statistics," March 2012. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/reliableandaffordableenergy/graphicsan

dcharts/usnucleargeneratingstatistics/. [Accessed 2 July 2012].

[3] Nuclear Energy Institute, "NEI: US Nuclear License Renewal Filings," June 2012. [Online].

Available:

http://www.nei.org/resourcesandstats/documentlibrary/reliableandaffordableenergy/graphicsan

dcharts/usnuclearlicenserenewalfilings/. [Accessed 2 July 2012].

[4] US Energy Information Administration, "EIA: How Old are US Nuclear Power Plants?," 16 May

2012. [Online]. Available: http://205.254.135.7/tools/faqs/faq.cfm?id=228&t=21. [Accessed 2

July 2012].

[5] Nuclear Energy Institute, "NEI: Nuclear Statistics," 2012. [Online]. Available:

http://www.nei.org/resourcesandstats/nuclear_statistics/usnuclearpowerplants/. [Accessed 2

July 2012].

[6] Nuclear Energy Institute, "NEI: Just the Facts," 2010. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/reliableandaffordableenergy/brochures

/justthefacts. [Accessed 2 July 2012].

[7] Nuclear Energy Institute, "NEI: White Papers," 15 April 2012. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/newplants/whitepaper/white-paper---

subsequent-license-renewal-creating-the-foundation-for-nuclear-plant-operation-beyond-60-

years/. [Accessed 15 June 2012].

[8] The 83rd Congress of the United States, "Atomic Energy Act of 1954," U.S. Atomic Energy

Commission , Washington, D.C., 1954.

[9] U.S. NRC, "NRC: Code of Federal Regulations," 13 June 2012. [Online]. Available:

http://www.nrc.gov/reading-rm/doc-collections/cfr/part050/part050-0066.html. [Accessed 22

June 2012].

[10] U.S. Nuclear Regulatory Commission, "NRC: Fact Sheet on Nuclear Reactor License Renewal,"

June 2012. [Online]. Available: http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/fs-

reactor-license-renewal.pdf. [Accessed 3 July 2012].

42

[11] U.S. NRC, "NUREG-1801 Generic Aging Lessons Learned Report," U.S. NRC, Washington, D.C.,

2012.

[12] Union of Concerned Scientists, "NRC License Renewal Issues," UCS, Cambridge, 2012.

[13] Y. Diaz, Interviewee, NRC Employee. [Interview]. 20 July 2012.

[14] G. R. Odette and G. E. Lucas, "Embrittlement of Nuclear Reactor Pressure Vessels," JOM, vol. 53,

no. 7, pp. 18-22, 2001.

[15] Electric Power Research Institute, "Life-Limiting Issues for Long-Term Operation of NPPs," EPRI,

Palo Alto, 2010.

[16] Department of Energy, "Lessons Learned from Davis-Besse Reactor Head Degradation,"

Department of Energy, Washington, D.C., 2002.

[17] J. Sielicki, "Davis-Besse to Shut Down for Replacement Vessel Head," 30 September 2011.

[Online]. Available: http://www.toledoblade.com/local/2011/09/30/Davis-Besse-to-shut-down-

for-replace-vessel-head.html. [Accessed 6 July 2012].

[18] L. Wroniewicz, "North Anna and Surry Reactor Vessel Head Replacements," Dominion Power,

Richmond, 2003.

[19] R. K. Nanstad, M. A. Sokolov, S. K. Iskander, A. A. Chernobaeva, Y. A. Nikolaev, A. M. Kryukov and

Y. N. Korolev, "Effects of Thermal Annealing and Reirradiation on Toughness of Reactor Pressure

Vessel Steels," in Proceedings of the 24th Water Reactor Safety Information Meeting, Bethesda,

1996.

[20] K. C. Wade, "Steam Generator Degradation and Its Impact on Continued Operation of Pressurized

Water Reactors in the United States," Energy Information Administration, 1995.

[21] P. D. L. Fillmore, "Literature Review of the Effects of Radiation and Temperature on the Aging of

Concrete," Idaho National Laboratory, Idaho Falls, 2004.

[22] D. J. Naus and B. R. Ellingwood, "Managing Concrete Structures Aging - One Approach," Oak Ridge

National Laboratory, Oak Ridge, 2001.

[23] Electric Power Research Institute, "Nondestructive Evaluation: Update on License Renewal One-

Time Inspection and Best NDE Practices," EPRI, Palo Alto, 2011.

[24] Y. Ohki, "nisa.jp," 2007. [Online]. Available:

http://nisaplm.jp/html/05_symposium/program/dl/S5-2.pdf. [Accessed 8 July 2012].

43

[25] Electric Power Research Institute, "Nuclear Plant Cable Aging Management in the U.S. with

Regard to Standards," EPRI, Washington, D.C., 2011.

[26] Nuclear Energy Institute, "Nuclear Power Plants Contribute Significantly to State and Local

Economies," NEI, Washington, D.C., 2012.

[27] U. O. o. N. N. Reactors, "NUREG-0468: Frequently Asked Questions About License Applications for

New Nuclear Reactors," US Nuclear Regulatory Commission, Washington, D.C., 2009.

[28] Nuclear Energy Institute, "Nuclear Energy's Economic Benefits - Past and Future," NEI,

Washington, D.C., 2011.

[29] Construction Innovation Forum, Diablo Canyon Power Plant Unit 1 Steam Generator

Replacement, Walbridge: Construction Innovation Forum, 2010.

[30] Nuclear Energy Institute, "Fuel/Refueling Outages," Nuclear Energy Institute, 2006. [Online].

Available: http://www.nei.org/resourcesandstats/nuclear_statistics/fuelrefuelingoutages/.

[Accessed 29 July 2012].

[31] Nuclear Energy Institute, Perspective on Public Opinion, Washington D.C.: NEI, 2012.

[32] US Energy Information Administration, "EIA: Total Energy Data," 27 June 2012. [Online].

Available: http://www.eia.gov/totalenergy/data/monthly/pdf/sec7_5.pdf. [Accessed 2 July 2012].

[33] US Energy Information Administration, "EIA: Nuclear Energy Overview," 27 June 2012. [Online].

Available: http://www.eia.gov/totalenergy/data/monthly/pdf/sec8_3.pdf. [Accessed 2 July 2012].

[34] NEI, "Emissions Avoided by the US Nuclear Industry (by year)," May 2012. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/protectingtheenvironment/graphicsand

charts/emissionsavoidedbytheusnuclearindustryyearly/. [Accessed 16 July 2012].

[35] NEI, "Environmentally Sound Nuclear Energy," 2003. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/protectingtheenvironment/brochures/e

cologybook2003/. [Accessed 16 July 2012].

[36] NEI, "Life Cycle Emissions Analysis," Nuclear Energy Institute, 2012. [Online]. Available:

http://nei.org/keyissues/protectingtheenvironment/lifecycleemissionsanalysis/. [Accessed 16

July 2012].

[37] D. Lochbaum, Interviewee, [Interview]. 28 June 2012.

[38] Nuclear Energy Institute, "Safely Managing Used Nuclear Fuel," NEI, Washington, D.C., 2010.

44

[39] J. Sapien, "ProPublica: Nuclear Waste," 30 March 2011. [Online]. Available:

http://www.propublica.org/article/while-nuclear-waste-piles-up-in-u.s.-billions-in-fund-to-

handle-it-sits-unu. [Accessed 19 July 2012].

[40] Union of Concerned Scientists, "How Coal Works," Union of Concerned Scientists, 2012. [Online].

Available: http://www.ucsusa.org/clean_energy/coalvswind/brief_coal.html. [Accessed 18 July

2012].

[41] Energy Information Administration, Annual Energy Review 2010, Washington D.C.: U.S. Energy

Information Administration, 2011.

[42] R. Howarth, D. Shindell, R. Santoro, A. Ingraffea, N. Phillips and A. Townsend-Small, "Methane

Emissions from Natural Gas Systems," Cornell University, Ithaca, 2012.

[43] World Nuclear Association, "Small Nuclear Power Reactors," WNA, 2012. [Online]. Available:

http://www.world-nuclear.org/info/inf33.html. [Accessed 18 July 2012].

[44] Union of Concerned Scientists, "ucsusa.org," 12 March 2012. [Online]. Available:

http://www.ucsusa.org/clean_energy/our-energy-choices/renewable-energy/. [Accessed 18 July

2012].

[45] S. Hargreaves, "First New Nuclear Reactor OK'd in Over 30 Years," 9 February 2012. [Online].

Available: http://money.cnn.com/2012/02/09/news/economy/nuclear_reactors/index.htm.

[Accessed 19 July 2012].

[46] J. Gaertner, 1 November 2010. [Online]. Available:

http://www.powermag.com/nuclear/Collaborative-Team-Investigates-Long-Term-Nuclear-

Operations_3101.html. [Accessed 14 June 2012].

[47] Nuclear Energy Institute, 15 January 2012. [Online]. Available:

http://www.nei.org/resourcesandstats/documentlibrary/newplants/whitepaper/myths--facts-

operating-reactors-beyond-40-years. [Accessed 1 June 2012].

[48] Nuclear Energy Institute, "NEI: Factsheet," 15 January 2012. [Online]. Available:

http://nei.org/resourcesandstats/documentlibrary/reliableandaffordableenergy/factsheet/nucle

arpowerplantcontributions/. [Accessed 2 June 2012].

[49] Nuclear Energy Institute, "NEI: White Papers," 15 April 2011. [Online]. Available:

http://nei.org/resourcesandstats/documentlibrary/newplants/whitepaper/jobs/. [Accessed 13

June 2012].

[50] U.S. NRC, "NRC: NUREG Staff Reports," 15 December 2010. [Online]. Available:

http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1801/r2/index.html. [Accessed

45

12 June 2012].

[51] U.S. NRC, "NRC: Code of Federal Regulations," 12 April 2012. [Online]. Available:

http://www.nrc.gov/reading-rm/doc-collections/cfr/part054/. [Accessed 20 June 2012].

[52] U.S. NRC, "NRC: Inspection Manual," 31 October 2008. [Online]. Available:

http://www.nrc.gov/reactors/operating/licensing/renewal/introduction/inspections/faq-

ip71003.html. [Accessed 18 June 2012].

[53] U.S. NRC, "NRC: NUREG-1850," 15 May 2006. [Online]. Available: http://www.nrc.gov/reading-

rm/doc-collections/nuregs/staff/sr1850/sr1850_faq_lr.pdf. [Accessed 20 June 2012].

[54] G. Carpenter, Interviewee, U.S. NRC Engineer. [Interview]. 14 June 2012.

[55] D. D. Aldrich, Interviewee, Associate Professor, Purdue University. [Interview]. 18 June 2012.

[56] NRC/DOE, "Life Beyond 60 Workshop Summary," Energetics Incorporated, Bethesda, 2008.

[57] The 79th Congress of the United States, "Atomic Energy Act of 1946," U.S. Atomic Energy

Commission, Washington, D.C., 1946.